1. Field of the Invention
This invention relates to an apparatus for applying surgical fasteners along an arcuate path in bodily areas otherwise difficult to reach with straight line fastener apparatus. More particularly, the invention relates to a fastener applying apparatus having an improved arcuately configured fastener cartridge and holder for the retainer portion of two-part surgical fasteners.
2. Background of the Prior Art
In some surgical operations it is necessary to fasten body tissue or to adjoin two hollow body organs alongside each other, with their longitudinal axes positioned generally parallel to each other, and to effect a longitudinal cut through the contacting circumferential walls of the two organs in order to open them to each other. After joining the two organs essentially constitute a single hollow chamber along the length of the cut. Correspondingly, the circumferential portions of the two adjoining organs on each lateral side of the cut must be sutured by at least one line of "stitches" in order to maintain the integrity of the union.
Instruments for this purpose are known in the art, and are described in U.S. Pat. Nos. 3,079,606, 3,490,675 and 3,499,591. Such instruments are generally referred to as linear cutting staplers and include two elongate fingers which are respectively insertable into the tissue or into each organ from an open end thereof such that the two fingers have the adjoining walls of the adjacent organs therebetween. Further examples of such instruments are disclosed in commonly assigned U.S. Pat. Nos. 4,429,695 and 4,520,817. The disclosures of these two last mentioned patents are incorporated herein by reference.
One of the fingers includes a disposable cartridge carrying a plurality of staples arranged in at least two lateral rows while the other finger includes an anvil for curling the staple legs into hook form upon being driven against the anvil. The stapling operation is effected by a pusher device which travels longitudinally along the cartridge carrying finger extending into one organ. The pusher mechanism acts simultaneously upon the staples at corresponding longitudinal positions in each lateral row, but successively acts upon the staples along the rows. For example, if two lateral rows of staples are provided, each row comprising twenty staples, the pusher means acts upon two staples at a time, one in each row, and successively acts upon each succeeding pair of staples.
Immediately behind the pusher means and laterally positioned between the staple rows is a knife member which severs the tissue or the facing adjoining walls of the two organs to thereby longitudinally open the two organs to each other between the rows of staples.
Up to the present these devices were limited to applying metal staples by means of a straight device which applies the fasteners along two or more straight line paths. For example, the apparatus disclosed in U.S. parent application Ser. No. 07/583,867 is a straight device. Two-part absorbable fasteners, such as those used in devices described in U.S. Pat. No. 4,665,916, hereby incorporated by reference, have been limited to devices which apply all of the fasteners simultaneously. Indeed, the retainer members of such absorbable fastener devices typically have been constructed as a web of retainers interconnected by flexible or frangible members. See, for example, U.S. Pat. No. 4,589,416. Devices of the type shown in the aforementioned U.S. Pat. Nos. 3,079,606; 3,490,675 and 3,499,591, on the other hand, employ an actuating cam bar which travels substantially perpendicularly to the direction of fastener motion to effect sequential placement of staples.
The advantage of applying fasteners while cutting adjacent tissue by curved devices to reach normally inaccessible portions of the body is clear. However, up to the present, the application of fasteners in the form of either deformable staples or two-part absorbable fasteners, accompanied by cutting, has been limited to straight instruments. In particular, maintaining the precise dimensional relation between components and providing accurate and precise spacing is peculiarly difficult with a curved apparatus. In addition, fasteners of the two-part type, i.e. fastener and retainer, present further difficulties and complications because of the need to provide precise alignment and movement of the fastener parts, an objective which has proved difficult even on straight devices.
The present invention relates to an apparatus which successfully combines a system of applying fasteners sequentially along an arcuate path while effecting complete closures in areas of the body previously inaccessible. Moreover, the present invention is applicable to fastener operations with and without cutting, while incorporating safety features which prevent unwanted movement of certain designated components during actuation of the apparatus.